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Tobacco use and its harmful health-related problems have become one of the largest modern preventable public health issues. Current research strongly suggests that smoking during adolescence enhances addictive smoking behaviors during life, which can be related to adolescence as a critical ontogenetic period characterized by behaviors that can increase the probability of risk-related behaviors such as sensation and novelty seeking. Adolescent development is also a period of maturation of frontal and subcortical neural systems, brain changes that underlie higher impulsivity tendencies to promote adequate learning and adaptations necessary to succeed the novel challenges of the adult life, but those changes also enhance vulnerabilities to the addictive effects of drugs. Consistent with this, tobacco use affects brain development processes which underlie longterm psychobiological alterations and the enhanced risks for tobacco addiction during adult life. Thus, the present review describes current psychobiological approaches to understand general addiction processes and tobacco addiction, highlighting the behavioral and neural short-term effects of tobacco use during adolescence and its long-term effects during adulthood. Current research has advanced on four aspects for the understanding of both the psychobiology of adolescent development and the effects of drugs of abuse during this time. The first aspect is behavioral, as adolescence is related to important changes on motivational and emotional behaviors such as sensation seeking. Other important behavioral changes are social approach, a higher variety of opportunity for personal choices, and development of personal independence. Research on a second aspect has focused on cognition. A review of research is presented showing enhanced abilities during adolescence development for reading, abstract and logical thinking, and novel problem solving. Stress reactivity is the third aspect of reviewed psychobiological mechanisms. The stress biological system undergoes important changes during adolescence, including changes on stress-related hormones and neural architecture. An important issue is that exposure to early and/or chronic stressful circumstances during adolescence could be related to higher risk to the start and maintenance of addiction states, as suggested by research assessing the disruptive effects of stress on psychobiological homeostatic processes needed to maintain stable biological and emotional regulation. The fourth aspect is psychobiology. In this section research is reviewed related to the development of monoaminergic brain circuits underlying motivation, novelty-seeking, impulsivity, and addiction processes. Using as model the previous review integration, the effects of nicotine are discussed, the essential addictive component of tobacco, on the neurochemical systems underlying tobacco addiction. Following this, important research is introduced that describes psychobiological changes during adolescence and evidence of vulnerability to addiction during this life stage. Then, current research on both short-term and long-term effects of tobacco or nicotine administration during adolescence on the brain, behavior, and cognition is introduced. The current research advances and discussions on the psychobiology of addictions in general, and tobacco addiction in particular, have been possible to a large extent from the use of animal models and preclinical research, since animal models have become crucial to identify learning, motivational, emotional, and cognitive mechanisms that underlie addictive processes, and making possible to perform experimental procedures to discover the functioning and participation of biological components. One example of such components is the cholinergic system, which is activated by nicotine and is part of the neurochemical machinery on different brain areas important for both tobacco addiction and adolescence development such as the dorsal striatum, amygdala, ventral tegmental area, nucleus accumbens, prefrontal cortex, and hippocampus. The present review and research divulgation written in Spanish are expected to clarify modern research on addiction and encourage current scientific education on the vulnerabilities and predispositions for tobacco abuse in Latin-American countries. [ABSTRACT FROM AUTHOR]

Introduction. The occasional consumption of nicotine can generate a dependency or addiction, being detectable through changes in neurobiological mechanisms. Objective. Contextualize from consumption to addiction and theoretically identify the neurobiological mechanism of transition from regular tobacco use to nicotine addiction. Methodology. A search for articles in English and Spanish was carried out using different databases and combinations of keywords, articles that described the characteristics of the neurobiological processes involved in the use or intermittent consumption of tobacco and nicotine addiction were selected. as the main theme. Results. The number of investigations related to this topic is reduced, even more in relation to the description of the processes and neural changes of nicotine addiction. Drug addiction is a complex neurobehavioral process that alters the circuits of the motivation-reward system of the brain, due to the decrease in dopamine and the affectation in the regulation of glutamate in the basal ganglia and extension of the amygdala is associated with the craving, anticipation, and deficits in executive function. Conclusions. Tobacco is considered a legal drug, so its consumption seems to be harmless. However, the evidence shows that its long-term consumption has serious consequences on the health of individuals. Understanding how occasional smoking changes to chronic use makes us more aware of adaptations in the brain. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the physical and psychological dependence to tobacco of Mexican smokers and its association with physical, psychological and social factors. Materials and methods. The 2016 National Alcohol and Tobacco Drug Consumption Survey (n=7 331) was analyzed using the Fagerström nicotine physical dependence scale (FTND) and the short scale of psychological dependence on tobacco (TAPDSc). Bivariate analyzes and generalized ordinal logistic regressions were performed to evaluate the associated factors. Results. 82.3% of daily smokers and 98.8% of occasional smokers reported mild physical dependence, while 47.9 and 37.9% respectively reported moderate psychological dependence. The age of initiation of tobacco use, drug use, high alcohol consumption and high emotional distress were associated with high levels of psychological dependence in all smokers. Conclusion. The exclusive use of FTND does not allow to adequately evaluate Mexican smokers. The physical and psychological dependence on tobacco should be assessed with independent and validated scales in this population. [ABSTRACT FROM AUTHOR]